And that it manages to be not insufferable while still being so predictable is a small tribute to its cast and crew.

The cast includes — in addition to the perpetually sagacious Freeman — Kris Kristofferson, Ashley Judd and Harry Connick Jr. All have been in better things, and should be again, but they’re certainly pleasant additions to the goings-on here.

Young Nathan Gamble, meanwhile — as our boy in love with a bottlenose — avoids the usual child-star traps, being neither tirelessly cute (a problem for one of his young co-stars) or tiresomely sullen. He seems like a nice but normal kid, and he helps take us on this journey.

It’s based — barely — on a true story about a dolphin named Winter. Rescued off the Florida coast, it seemed too badly injured to live. Until its medical team began to wonder: People with disabilities get prosthetic limbs. Why not give a disabled dolphin a prosthetic tail?

Of course it got a bit more complicated than that — dolphins aren’t exactly good with buckling things on (or wearing them for long). And the screenplay gets even more complicated as it introduces all sorts of fictional elements to turn this story into a movie.

Perhaps it’s because he starred, years ago, in a very nice nature film, “Never Cry Wolf.” Perhaps it’s because “Air Bud” — a family film starring a golden retriever, which my own children once kept on heavy rotation at home — is among his directing credits.

But whatever the reason, Smith knows how to handle things.

He doesn’t overplay the troubled-kid melodrama while still nicely emphasizing the human/beast bond. And several otherworldly sequences — one featuring some beautiful underwater photography, and another showing whimsically dancing blueprints — jump off the screen, even if you aren’t seeing this film at one of its 3-D engagements.

Not quite as three-dimensional are some of the script’s third-act developments, which include a disabled little girl, an injured hero’s war story, several inspirational speeches and a hurricane. By the time of a last-ditch fundraising attempt, it’s all a little exhausting — at least, if you’re trying to tote up all the clichés.

But most of it will be new to grade schoolers. And if you’re the accompanying guardian, thanks to Smith and Co., little of it will be hard to take.